CN113905507A

CN113905507A - Low warpage PCB transition structure

Info

Publication number: CN113905507A
Application number: CN202111195238.0A
Authority: CN
Inventors: 修威; 田海燕; 杨光; 李亮; 吴迪; 韩运皓
Original assignee: Beijing Huameta Technology Co ltd
Current assignee: Beijing Huameta Technology Co ltd
Priority date: 2021-10-13
Filing date: 2021-10-13
Publication date: 2022-01-07
Anticipated expiration: 2041-10-13
Also published as: CN113905507B

Abstract

The invention discloses a low-warpage PCB transition structure, which comprises a first PCB, a metal structural part and a second PCB, wherein a radio frequency insulator is arranged in the metal structural part, countersunk holes are formed in the first PCB and the second PCB, a blind hole is formed in the metal structural part, an upper layer screw fixes the first PCB on the upper surface of the metal structural part through the countersunk hole in the first PCB and the blind hole in the metal structural part, a lower layer screw fixes the second PCB on the lower surface of the metal structural part through the countersunk hole in the second PCB and the blind hole in the metal structural part, and the first PCB and the second PCB are connected through the radio frequency insulator; according to the invention, the external PCB is fixed on the high-flatness metal structural member by the screws through the countersunk head via hole technology, so that the warping degree of the PCB is reduced, the surface flatness of the PCB is improved, and the PCB is well attached to the glass substrate.

Description

Low warpage PCB transition structure

Technical Field

The invention relates to the technical field of radio frequency signal transmission, in particular to a low-warpage PCB transition structure.

Background

The phase shifter is a core device of the T/R component, and the performance, power consumption, size and the like of the phase shifter have decisive influence on system indexes of the phased array antenna. The traditional phase shifter chip has the advantages of complex design, high production cost, large packaging structure and poor product consistency. The novel metamaterial phase shifter represented by the liquid crystal phase shifter has the characteristics of low cost, low power consumption, good mass production consistency and the like, and gradually becomes a technical hotspot.

To achieve rapid response of the liquid crystal phase shifter, a low cell thickness structure is generally required, and thus a high flatness liquid crystal sealing material is required. Generally, glass is selected as a packaging material for liquid crystal materials due to its characteristics of low loss tangent angle and high surface flatness. On one hand, liquid crystal is required to be completely sealed as a liquid material, and on the other hand, the technology for manufacturing the metalized through hole in the glass is not mature. The liquid crystal phase shifter is generally located in upper and lower glass substrates that seal the liquid crystal, and the input and output of the phase shifter signal become pain points for the liquid crystal phase shifter to use in the T/R module. The power distribution network from the T/R component to the total port is completely placed in the liquid crystal box, so that the transmission loss of the power distribution network is increased; the power distribution network is placed on the surface of the glass, and the defects that the surface wave loss is large, the active amplifier cannot be attached to the surface of the glass and the like exist; the transmission loss can be reduced by placing the power distribution network on an external PCB and then attaching the power distribution network to the outer surface of the glass, and an active amplifier device is attached, however, the flatness introduced by the warping degree of the conventional PCB is far less than that of the surface of the glass, and seamless attachment cannot be realized after attachment, so that the consistency of network signals is poor.

Disclosure of Invention

Therefore, the embodiment of the invention provides a low-warpage PCB transition structure to solve the problem that the input and output of phase shifter signals become pain points of a liquid crystal phase shifter used in a T/R assembly in the prior art.

In order to achieve the above object, the embodiments of the present invention provide the following technical solutions:

the utility model provides a low angularity PCB transition structure, includes first PCB board, metallic structure and second PCB board, be equipped with the radio frequency insulator in the metallic structure, first PCB board with all be equipped with the counter sink on the second PCB board, the last blind hole that is equipped with of metallic structure, upper screw pass through counter sink on the first PCB board with blind hole on the metallic structure will first PCB board is fixed metallic structure upper surface, lower floor's screw passes through counter sink on the second PCB board with blind hole on the metallic structure will the second PCB board is fixed the metallic structure lower surface, first PCB board with the second PCB board passes through the radio frequency insulator is connected.

Preferably, the first PCB and the second PCB are both provided with conductive vias.

Preferably, a coupling line is arranged on the first PCB, one end of the coupling line is connected with the conductive via hole on the first PCB, and the other end of the coupling line is used for coupling a device signal into the low warpage PCB transition structure.

Preferably, a second transmission line is arranged on the second PCB, one end of the second transmission line is connected to the conductive via hole on the second PCB, and the other end of the second transmission line is used for outputting a signal coupled into the low warpage PCB transition structure.

Preferably, the radio frequency isolator further comprises a first metal floor, the first metal floor is located between the first PCB and the metal structural member, a first transmission line is arranged on the first metal floor, one end of the first transmission line is connected with the conductive through hole in the first PCB, and the other end of the first transmission line is connected with the radio frequency insulator.

Preferably, a groove is formed in the metal structural part, and the groove is formed in a position where the metal structural part is in contact with the first transmission line.

Preferably, the PCB further comprises a second metal floor, and the second metal floor is located between the second PCB and the metal structural member.

Preferably, the blind hole is internally provided with threads, and the first PCB and the second PCB are fixed on the metal structural member through the threads by screws.

The invention has at least the following beneficial effects: the invention provides a low-warpage PCB transition structure, which comprises a first PCB, a metal structural part and a second PCB, wherein a radio frequency insulator is arranged in the metal structural part, countersunk holes are formed in the first PCB and the second PCB, blind holes are formed in the metal structural part, an upper layer screw fixes the first PCB on the upper surface of the metal structural part through the countersunk hole in the first PCB and the blind hole in the metal structural part, a lower layer screw fixes the second PCB on the lower surface of the metal structural part through the countersunk hole in the second PCB and the blind hole in the metal structural part, and the first PCB and the second PCB are connected through the radio frequency insulator; according to the invention, the external PCB is fixed on the high-flatness metal structural member by the screws through the countersunk head via hole technology, so that the warping degree of the PCB is reduced, the surface flatness of the PCB is improved, and the PCB is well attached to the glass substrate.

Drawings

In order to more clearly illustrate the prior art and the present invention, the drawings which are needed to be used in the description of the prior art and the embodiments of the present invention will be briefly described. It should be apparent that the drawings in the following description are merely exemplary, and that other drawings may be derived from the provided drawings by those of ordinary skill in the art without inventive effort.

The structures, proportions, sizes, and other dimensions shown in the specification are for illustrative purposes only and are not intended to limit the scope of the present invention, which is defined by the claims, and it is to be understood that all such modifications, changes in proportions, or alterations in size which do not affect the efficacy or objectives of the invention are not to be seen as within the scope of the present invention.

Fig. 1 is a schematic diagram of a transition structure of a low warpage PCB according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an antenna unit according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a phase shifter unit according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a liquid crystal-PCB coupling structure according to an embodiment of the present invention.

Description of reference numerals:

1-a first PCB board; 11-coupled lines; 12-a first counterbore; 13-a first conductive via; 2-a metal structural member; 21-a radio frequency insulator; 22-blind hole; 23-a groove; 3-a second PCB board; 31-a second transmission line; 32-a second counterbore; 33-a second conductive via; 4-a first metal floor; 41-a first transmission line; 5-a second metal floor; 6-radiation piece; 7-radiation seam; 8-a radiating transmission line; 9-metal floor; 10-IT0 bias line; 101-a liquid crystal phase shifter; 102-liquid crystal coupled lines; 103-slot gap.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In the description of the present invention, "a plurality" means two or more unless otherwise specified. The terms "first," "second," "third," "fourth," and the like in the description and claims of the present invention and in the above-described drawings (if any) are intended to distinguish between referenced items. For a scheme with a time sequence flow, the term expression does not need to be understood as describing a specific sequence or a sequence order, and for a scheme of a device structure, the term expression does not have distinction of importance degree, position relation and the like.

Furthermore, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements specifically listed, but may include other steps or elements not expressly listed that are inherent to such process, method, article, or apparatus or that are added to a further optimization scheme based on the present inventive concept.

Referring to fig. 1, the present invention provides a low warpage PCB transition structure, including a first PCB 1, a metal structural member 2 with a threaded blind hole 22, and a second PCB 3, where the metal structural member 2 is a high flat structural member, a radio frequency insulator 21 is disposed in the metal structural member 2, countersunk holes are disposed on the first PCB 1 and the second PCB 3, the countersunk hole on the first PCB 1 is a first countersunk hole 12, the countersunk hole on the second PCB 3 is a second countersunk hole 32, and at least two of the first countersunk hole 12 and the second countersunk hole 32 are provided; an upper layer screw penetrates through the first counter sink 12 on the first PCB 1 and is fixed in the blind hole 22 on the metal structural member 2, and the first PCB 1 is fixed on the upper surface of the metal structural member 2; a lower layer screw penetrates through a second counter bore 32 of the second PCB 3 and is fixed in the blind hole 22 of the metal structural member 2, the second PCB 3 is fixed on the lower surface of the metal structural member 2, the screw has double functions of fixing and positioning, and the counter bores on the first PCB 1 and the second PCB 3 sink into the fixing screw, so that the condition that a nut protrudes out of the PCB plane to influence the bonding of the PCB and the glass is avoided; the first PCB 1 and the second PCB 3 are connected by a radio frequency insulator 21 placed inside the metal structural member 2. The first PCB 1, the metal structural part 2 and the second PCB 3 form a high-flatness PCB structural component, and excellent bonding with a glass substrate is realized; according to the invention, the first PCB 1, the radio frequency insulator 21 and the second PCB 3 are tightly combined by adopting screw pressing, the structure is simple, and complex processes such as welding and the like are avoided.

The invention provides a low warping degree PCB transition structure, which further comprises a first metal floor 4 and a second metal floor 5, wherein the first metal floor 4 is positioned between a first PCB 1 and a metal structural part 2, and a layer of the second metal floor 5 is positioned between a second PCB 3 and the metal structural part 2; the first metal floor 4 is provided with a first transmission line 41, the first PCB board 1 and the second PCB board 3 are both provided with conductive through holes, the conductive through hole on the first PCB board 1 is a first conductive through hole 13, and the conductive through hole on the second PCB board 3 is a second conductive through hole 33; one end of the first transmission line 41 is connected with the first conductive via hole 13 on the first PCB board 1, and the other end is connected with the radio frequency insulator 21; be equipped with recess 23 on the metallic structure spare 2, recess 23 is located the position of first transmission line 41 with the contact of metallic structure spare 2, has both avoided first transmission line 41 radiation loss, promotes transmission efficiency, still avoids metallic structure spare 2 to be connected with first transmission line 41.

A coupling line 11 is arranged on the first PCB 1, one end of the coupling line 11 is connected with a first conductive via hole 13 on the first PCB 1, and the other end is used for coupling a device signal into the low warpage PCB transition structure; a second transmission line 31 is disposed on the second PCB 3, one end of the second transmission line 31 is connected to the second conductive via 33 on the second PCB 3, and the other end is used for outputting a signal coupled into the low warpage PCB transition structure.

To more clearly and clearly illustrate the present invention, embodiments of the present invention provide a liquid crystal antenna based on a low warpage PCB transition structure.

Referring to fig. 2 to 3, the liquid crystal antenna includes a low warpage PCB transition structure, a radiation sheet 6, a first glass substrate, a liquid crystal phase shifter 101, a liquid crystal layer, a metal floor 9, and a second glass substrate.

The signal is received by the antenna unit to one end of the liquid crystal phase shifter 101, and the liquid crystal phase shifter 101 is composed of a radiation transmission line 8, an ITO bias line 10 and a metal floor 9. The ITO bias line 10 and the radiation transmission line 8 are positioned at the bottom layer of the first glass substrate and are first electrodes; the metal floor 9 is located on the top layer of the second glass substrate and is a second electrode. The ITO bias line 10 loads voltage between the radiation transmission line 8 and the metal floor 9, liquid crystal molecules in the liquid crystal layer are controlled to deflect, the relative dielectric constant of liquid crystal is changed, and then the transmission line phase shifting is achieved.

Referring to fig. 4, the other end of the liquid crystal phase shifter 101 is connected to the liquid crystal coupling line 102. The liquid crystal coupling line 102, the slot 103 on the metal floor 9 of the liquid crystal phase shifter 101 and the PCB coupling line 11 on the top layer of the first PCB 1 constitute a liquid crystal-PCB coupling structure. This structure can realize that a signal is guided to the coupling line 11 on the first PCB board 1 by the liquid crystal phase shifter 101.

The signal is then routed by the first conductive via 13 located inside the first PCB board 1 to the first transmission line 41 on the first metal floor 4. The radio frequency insulator 21 guides the signal of the first transmission line 41 to the second conductive via hole 33 positioned inside the second PCB 3, and the second conductive via hole 33 is connected with the second transmission line 31, so that the signal is guided to the second transmission line 31 by the antenna unit, the signal transmission of the whole system is realized, and the influence of the device radiation, which is possibly introduced after an active device is additionally arranged on the second transmission line 31, on the antenna radiation is effectively reduced.

The above specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments.

All the technical features of the above embodiments can be arbitrarily combined (as long as there is no contradiction between the combinations of the technical features), and for brevity of description, all the possible combinations of the technical features in the above embodiments are not described; these examples, which are not explicitly described, should be considered to be within the scope of the present description.

The present invention has been described in considerable detail by the general description and the specific examples given above. It should be noted that it is obvious that several variations and modifications can be made to these specific embodiments without departing from the inventive concept, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a low angularity PCB transition structure, a serial communication port, including first PCB board, metallic structure and second PCB board, be equipped with the radio frequency insulator in the metallic structure, first PCB board with all be equipped with the counter sink on the second PCB board, the last blind hole that is equipped with of metallic structure, upper screw pass through counter sink on the first PCB board with blind hole on the metallic structure will first PCB board is fixed metallic structure upper surface, lower floor's screw passes through counter sink on the second PCB board with blind hole on the metallic structure will the second PCB board is fixed the metallic structure lower surface, first PCB board with the second PCB board passes through the radio frequency insulator is connected.

2. The low warpage PCB transition structure of claim 1, wherein the first PCB board and the second PCB board are both provided with conductive vias.

3. The low warpage PCB transition structure of claim 2, wherein a coupling line is disposed on the first PCB, one end of the coupling line is connected to the conductive via on the first PCB, and the other end is used for coupling a device signal into the low warpage PCB transition structure.

4. The low warpage PCB transition structure of claim 2, wherein a second transmission line is disposed on the second PCB, one end of the second transmission line is connected to the conductive via on the second PCB, and the other end is used for outputting a signal coupled into the low warpage PCB transition structure.

5. The PCB transition structure with low warpage according to claim 1, further comprising a first metal floor, wherein the first metal floor is located between the first PCB and the metal structure, a first transmission line is disposed on the first metal floor, one end of the first transmission line is connected to the conductive via hole on the first PCB, and the other end of the first transmission line is connected to the radio frequency insulator.

6. The low warpage PCB transition structure of claim 5, wherein a groove is provided on the metal structure member, and the groove is provided at a position where the metal structure member contacts the first transmission line.

7. The low warpage PCB transition structure of claim 1, further comprising a second metal floor, the second metal floor being located between the second PCB board and the metal structural member.

8. The low warpage PCB transition structure of claim 1, wherein a thread is provided in the blind hole, and a screw fixes the first and second PCBs on the metal structure member through the thread.